DB2 Sprockets and Alternatives? - Ducati.ms

Desmo_Demon · Sep 15th, 2011, 7:50 pm

It appears that the sprockets on my 1994 DB2 are not aligned very well. From what I've read through some Internet searches, the front sprocket should have a 3.5-4mm offset toward the outside of the bike. IIRC, this is about the same as an '87-'88 Paso 750, but I'll have to double-check on that. From what I can tell without tearing the bike apart, mine has a 0-offset front sprocket (which is quite common on the majority of Ducati bikes).

For the rear sprocket, is there a more common bike with a sprocket that will fit, or do I have to order one specifically for the rims (Dymag?....Marvic?...Oscam?) on the bike?

Ricoyam · Sep 17th, 2011, 2:08 am

Not sure if there is anything that will just bolt up. If I was needing a sprocket, I would give Sprocket Specialist a call. With any luck they'll have the pattern for the mounting. They'll also custom drill what you need. If you have access to a mill it's pretty simple to do and it can be done on a drill press with a bit of care.

Desmo_Demon · Sep 18th, 2011, 12:56 pm

Quote:

Originally Posted by Ricoyam

Not sure if there is anything that will just bolt up.

Yeah, I figure the worse case scenario is to have to have a stock Ducati front sprocket machined for the offset and find a 5-bolt rear sprocket with the correct hub hole and then redrill the mounting holes (of have to machine the hub hole diameter and redrill). Jim believes he has his old take-off front sprocket that I can borrow to take measurements for the offset.

I don't like having misaligned sprockets, so I think I'll park the bike until I at least get the front sprocket swapped to realign everything.

Edit #1 - Silly me. I went back and looked at my rear sprocket on the bike and it is a Vortex Part #841A-39. Going to their website, they offer many different teeth options for this part number, but....it doesn't state the application of the sprocket. Anyone know of a cross-reference table by part #? I prefer steel for a rear sprocket. I could spend a few extra dollars and have Supersporx make one for me, as an option. I like the way theirs look, and I could get a red anodized carrier.

Edit #2 - Surfing around I have found this sprocket listed as being for Marchesini, BST, Bito Magtan, and PVM SBK wheels and the specifications are...

Bolt circle (diameter) - 5 bolt @ 100 mm
Bolt hole diameter - 10.5 mm
Hub ID (inner hole for hub) - 80 mm

Motowheels has Supersprox sprockets in stock that will fit. Now to find a front sprocket.

Desmo_Demon · Dec 16th, 2011, 1:07 pm

Son of an effin' MoFo.......

Finally got the chain and sprockets taken care of by getting the rear sprocket directly from Supersprox and having a buddy machine the front sprocket. With the way the weather's been, I finally got around to getting the bike back together last week. I was wanting to do a shakedown run this afternoon, with plans of riding the bike this weekend, and....

an effin FCR is spewing gas out the overflow, tapping the carb bodies won't make it stop, and I can't figure out which carb it is.

Looks like I have to pull all the GD effin fairing off the bike and mess with the dern carbs. I guess I'll ride the 748 this weekend.

daotoys1 · Dec 16th, 2011, 1:56 pm

If the front sprocket is to far inward toward the engine, you can always use shims and/or a collar/spacer to get the correct alinement to the rear sprocket. I have done this with my SB8RS bikes .

BIMOTA by using a donor engine and putting it into its own rolling chassis has been known to do a few different things regarding sprocket alignments. They have used front sprocket spacers/shims as well as having a sprocket supplier make them a custom sprocket with its own specs.

On the 3 SB8RS bikes I have the BIMOTA front sprocket is unique . So I buy Suzuki TL 520 sprockets and shim them out to line up to the rear sprocket. The only other option would be to contact BIMOTA and buy one of their sprockets for alot more $$$$$$.

I know that BIMOTA has used AFAM for a number of its sprockets on different models. Some of these AFAM sprockets have a BIMOTA logo on them, some are not marked and some have AFAM logo with or without the BIMOTA logo......

Sprocket Specialists is a good lead....they will do anything you need and for a reasonable price too.

good luck.

Do you need just a front sprocket or a rear or both????

My email is ;

dougolmstedotr@hotmail.com

If you tell me what you need and send me a few pictures of the sprockets that are on or came off your bike Ill look to see if I have what you need in my parts inventory.

DAO

Desmo_Demon · Dec 16th, 2011, 2:18 pm

Quote:

Originally Posted by daotoys1

Do you need just a front sprocket or a rear or both????

The rear sprocket is an off-the-shelf item if you know what you are looking for. I bought a rear sprocket directly from Supersporx and had two Ducati front sprockets machined. It took a total of about two months, but I finally got the sprockets taken care of.

Ricoyam · Dec 17th, 2011, 2:42 pm

Quote:

Originally Posted by Desmo_Demon

Son of an effin' MoFo.......

Finally got the chain and sprockets taken care of by getting the rear sprocket directly from Supersprox and having a buddy machine the front sprocket. With the way the weather's been, I finally got around to getting the bike back together last week. I was wanting to do a shakedown run this afternoon, with plans of riding the bike this weekend, and....

an effin FCR is spewing gas out the overflow, tapping the carb bodies won't make it stop, and I can't figure out which carb it is.

Looks like I have to pull all the GD effin fairing off the bike and mess with the dern carbs. I guess I'll ride the 748 this weekend.

Ain't that the way things go......?
I've never had a overflow problem on an FCR but I guess there's always a first time. I haven't ridden my DB for a while and will try to get it out his afternoon. Wish me luck, knocking on wood.

ChrisE · Feb 21st, 2012, 3:36 pm

The rear sprocket is the same as a GSXR750, I think model year 1997.

You just need the inner/center whole diameter and the diameter of the mounting studs and you should be able to find the appropriate model year.

I have a Vortex 39T on the back of mine.

Desmo_Demon · Feb 23rd, 2012, 2:06 am

Quote:

Originally Posted by ChrisE

The rear sprocket is the same as a GSXR750, I think model year 1997.

You just need the inner/center whole diameter and the diameter of the mounting studs and you should be able to find the appropriate model year.

I tried that originally, and every GSXR sprocket I was finding had a 76mm ID for the hub. I'd actually considered machining the DB2's sprocket carrier to 76mm so I could use the vast majority of GSXR sprockets....until I found the off-the-shelf Supersprox.

I removed a Vortex and have no intentions of running aluminum sprockets.

With you in TN, are you a member of US Desmo? If not, you need to join the club and come to some of the get togethers. The club President and I had our DB2 bikes at the Ducks Fly South rally this past September.